<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1409-2433</journal-id>
<journal-title><![CDATA[Revista de Matemática Teoría y Aplicaciones]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. Mat]]></abbrev-journal-title>
<issn>1409-2433</issn>
<publisher>
<publisher-name><![CDATA[Centro de Investigaciones en Matemática Pura y Aplicada (CIMPA) y Escuela de Matemática, San José, Costa Rica.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1409-24332011000200002</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Un algoritmo genético para un problema de horarios con restricciones especiales]]></article-title>
<article-title xml:lang="en"><![CDATA[A genetic algorithm in a schedule problem with special constraints]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Pérez de la Cruz]]></surname>
<given-names><![CDATA[Carlos]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ramírez Rodríguez]]></surname>
<given-names><![CDATA[Javier]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Nacional Autónoma de México Posgrado en Ingeniería en Sistemas ]]></institution>
<addr-line><![CDATA[ México D. F.]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad Autónoma Metropolitana Departamento de Sistemas ]]></institution>
<addr-line><![CDATA[ México D. F.]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2011</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2011</year>
</pub-date>
<volume>18</volume>
<numero>2</numero>
<fpage>215</fpage>
<lpage>229</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1409-24332011000200002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1409-24332011000200002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1409-24332011000200002&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[En Ramírez (2001) se introdujo el problema de coloracion robusta generalizado (PCRG), el cual resuelve problemas de horarios que consideran restricciones del tipo: dos eventos no pueden realizarse a la misma hora y debe haber al menos d días entre dos eventos. El PCRG es una coloración robusta, en que dada una gráfica y un número fijo de colores, no necesariamente el número cromático, considera la distancia entre colores como penalización de las aristas complementarias. Se demostró que el problema es NP-Completo, por lo que es necesario utilizar métodos aproximados para encontrar buenas soluciones en un tiempo razonable. En este trabajo se presenta un híbrido de un algoritmo genético con uno de búsqueda local para casos de 30 a 120 horas por semana, se demuestra que para algunos la solución es óptima y en otros se encuentran soluciones muy prometedoras.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Ramírez (2001) introduced the generalized robust coloring problem (GRCP), this problem lets solve timetabling problems which considers constraints such as: two events can not be assigned at the same time and there must be at least d days between two events. The GRCP deals with a robust coloring for a given graph with a fixed number of colors, not necessarily the chromatic number and considers the distance between colors as the penalization of complementary edges. It was shown that the problem is NP-complete, so it is necessary to use approximate methods to find good solutions in a reasonable time. This paper presents a hybrid of a genetic algorithm with a local search for cases of 30-120 hours per week; it is shown that for some cases the found solution is optimal and in other cases the solutions are very promising.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[horarios]]></kwd>
<kwd lng="es"><![CDATA[restricciones especiales]]></kwd>
<kwd lng="es"><![CDATA[heuristícas]]></kwd>
<kwd lng="en"><![CDATA[timetabling]]></kwd>
<kwd lng="en"><![CDATA[special constrains]]></kwd>
<kwd lng="en"><![CDATA[heuristics]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <div style="text-align: center;"><font size="4"> <span style="font-family: verdana; font-weight: bold;">Un algoritmo gen&eacute;tico para un problema de horarios con restricciones especiales</span></font><br  style="font-family: verdana; font-weight: bold;"> <br style="font-family: verdana; font-weight: bold;"> <font size="4"><span style="font-family: verdana; font-weight: bold;">A genetic algorithm in a schedule problem with special constraints</span></font><br  style="font-family: verdana;"> </div> <font size="2"><br style="font-family: verdana;"> </font>     <div style="text-align: justify;"><font size="2"><span  style="font-family: verdana;">Carlos P&eacute;rez de la Cruz<a  href="#autor1"><sup>*</sup></a></span></font><br  style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;">Javier Ram&iacute;rez Rodr&iacute;guez<a href="#autor2"><sup>&#8224;</sup></a></span></font><br  style="font-family: verdana;"> </div> <font size="2"><br style="font-family: verdana;"> <span style="font-family: verdana;"><a name="autor1"></a>*Posgrado en Ingenier&iacute;a en Sistemas, Universidad Nacional Aut&oacute;noma de M&eacute;xico, Circuito Exterior, Ciudad Universitaria, M&eacute;xico D. F., M&eacute;xico. E-Mail: <a href="mailto:larsoinde@hotmail.com">larsoinde@hotmail.com</a></span><br  style="font-family: verdana;"> <span style="font-family: verdana;"><a name="autor2"></a>&#8224;Departamento de Sistemas, Universidad Aut&oacute;noma Metropolitana &#8211; Azcapotzalco. Avenida San Pablo 180, Colonia Reynosa Tamaulipas, 02200 M&eacute;xico D. F., M&eacute;xico. E-Mail: <a  href="mailto:jararo@correo.azc.uam.mx">jararo@correo.azc.uam.mx</a>    <br>     <br> <a href="#correspondencia">Direcci&oacute;n para correspondencia</a><br  style="font-family: verdana;"> </span><br style="font-family: verdana;"> </font>     <div style="text-align: justify;"><font size="3"><span  style="font-family: verdana; font-weight: bold;"></span></font> <hr style="width: 100%; height: 2px;"><font size="3"><span  style="font-family: verdana; font-weight: bold;">Resumen</span></font><br  style="font-family: verdana;"> <br style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;">En Ram&iacute;rez (2001) se introdujo el problema de coloracion robusta generalizado (PCRG), el cual resuelve problemas de horarios que consideran restricciones del tipo: dos eventos no pueden realizarse a la misma hora y debe haber al menos d d&iacute;as entre dos eventos. El PCRG es una coloraci&oacute;n robusta, en que dada una gr&aacute;fica y un n&uacute;mero fijo de colores, no necesariamente el n&uacute;mero crom&aacute;tico, considera la distancia entre colores como penalizaci&oacute;n de las aristas complementarias. Se demostr&oacute; que el problema es NP-Completo, por lo que es necesario utilizar m&eacute;todos aproximados para encontrar buenas soluciones en un tiempo razonable. En este trabajo se presenta un h&iacute;brido de un algoritmo gen&eacute;tico con uno de b&uacute;squeda local para casos de 30 a 120 horas por semana, se demuestra que para algunos la soluci&oacute;n es &oacute;ptima y en otros se encuentran soluciones muy prometedoras. </span></font><br style="font-family: verdana;"> <br style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;"><span  style="font-weight: bold;">Palabras clave:</span> horarios; restricciones especiales; heurist&iacute;cas.</span></font><br  style="font-family: verdana;"> <br style="font-family: verdana;"> <font size="3"><span style="font-family: verdana; font-weight: bold;">Abstract</span></font><br  style="font-family: verdana;"> <br style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;">Ram&iacute;rez (2001) introduced the generalized robust coloring problem (GRCP), this problem lets solve timetabling problems which considers constraints such as: two events can not be assigned at the same time and there must be at least d days between two events. The GRCP deals with a robust coloring for a given graph with a fixed number of colors, not necessarily the chromatic number and considers the distance between colors as the penalization of complementary edges. It was shown that the problem is NP-complete, so it is necessary to use approximate methods to find good solutions in a reasonable time. This paper presents a hybrid of a genetic algorithm with a local search for cases of 30-120 hours per week; it is shown that for some cases the found solution is optimal and in other cases the solutions are very promising.</span></font><br style="font-family: verdana;"> <br style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;"><span  style="font-weight: bold;">Keywords:</span> timetabling; special constrains; heuristics.</span></font><br style="font-family: verdana;"> <br style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;"><span  style="font-weight: bold;">Mathematics Subject Classification: </span>05C15, 90C59, 68T20.    <br>     <br> </span></font> <hr style="width: 100%; height: 2px;">    <br> <font size="2"><span style="font-family: verdana;">Ver contenido disponible en pdf</span></font><br style="font-family: verdana;"> <font size="2"><span style="font-family: verdana;"></span></font>    <br> <hr style="width: 100%; height: 2px;">     <p><font size="3"><span style="font-family: verdana; font-weight: bold;">Referencias</span></font></p>     ]]></body>
<body><![CDATA[<br>     <p><font size="2"><span style="font-family: verdana;">[1] Lara, P.; L&oacute;pez, R.; Ram&iacute;rez, J.; Y&aacute;&ntilde;ez, J. (2010) &#8220;SA model for timetabling problems with period spread constraints&#8221;, Journal of Operational Research Society 173: 1&#8211;6.</span></font>    <!-- ref --><br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=1953021&pid=S1409-2433201100020000200001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p><font size="2"><span style="font-family: verdana;">[2] Ram&iacute;rez-Rodr&iacute;guez, J. (2001) Extensiones del Problema de Coloraci&oacute;n de Grafos. Tesis de Doctorado, Universidad Complutense de Madrid, Madrid.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=1953022&pid=S1409-2433201100020000200002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></span></font></p>     <!-- ref --><p><font size="2"><span style="font-family: verdana;">[3] Grimaldi, R. (2009) Matem&aacute;ticas Discreta y Combinatoria, Una introducci&oacute;n con Aplicaciones. Prentice Hall, M&eacute;xico.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=1953024&pid=S1409-2433201100020000200003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></span></font></p>     <!-- ref --><p><font size="2"><span style="font-family: verdana;">[4] Y&aacute;&ntilde;ez, J.; Ram&iacute;rez, J. (2003) &#8220;The Robust Coloring Problem&#8221;, European Journal of Operational Research 148(3): 546&#8211;558.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=1953026&pid=S1409-2433201100020000200004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --> </span></font></p> <font size="2">    <br> <a name="correspondencia"></a><!-- big --><!-- big -->Correspondencia a: <!-- /big --><!-- /big --></font><font  size="2"><span style="font-family: verdana;">Carlos P&eacute;rez de la Cruz. </span></font><font size="2"><span style="font-family: verdana;">Posgrado en Ingenier&iacute;a en Sistemas, Universidad Nacional Aut&oacute;noma de M&eacute;xico, Circuito Exterior, Ciudad Universitaria, M&eacute;xico D. F., M&eacute;xico. E-Mail: <a href="mailto:larsoinde@hotmail.com">larsoinde@hotmail.com</a></span></font> </div> <font size="2"><span style="font-family: verdana;">Javier Ram&iacute;rez Rodr&iacute;guez. </span></font><font size="2"><span  style="font-family: verdana;">Departamento de Sistemas, Universidad Aut&oacute;noma Metropolitana &#8211; Azcapotzalco. Avenida San Pablo 180, Colonia Reynosa Tamaulipas, 02200 M&eacute;xico D. F., M&eacute;xico. E-Mail: <a  href="mailto:jararo@correo.azc.uam.mx">jararo@correo.azc.uam.mx</a>    ]]></body>
<body><![CDATA[<br> </span></font>     <div style="text-align: center;"><font size="2"><span  style="font-family: verdana;"></span></font> <hr style="width: 100%; height: 2px;"><font size="2"><span  style="font-family: verdana;">Received: 23 Feb 2010; Revised: 23 Nov 2010; Accepted: 1 Feb 2011</span></font>    <br> </div>      ]]></body><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lara]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[López]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Ramírez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Yáñez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[SA model for timetabling problems with period spread constraints]]></article-title>
<source><![CDATA[Journal of Operational Research Society]]></source>
<year>2010</year>
<volume>173</volume>
<page-range>1-6</page-range></nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ramírez-Rodríguez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Extensiones del Problema de Coloración de Grafos]]></source>
<year>2001</year>
</nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Grimaldi]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<source><![CDATA[Matemáticas Discreta y Combinatoria, Una introducción con Aplicaciones]]></source>
<year>2009</year>
<publisher-name><![CDATA[Prentice Hall]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yáñez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Ramírez]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[The Robust Coloring Problem]]></article-title>
<source><![CDATA[European Journal of Operational Research]]></source>
<year>2003</year>
<volume>148(3)</volume>
<page-range>546-558</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
